1. Field of the Invention
The present invention relates generally to electrode assemblies and, more particularly, to a non-communicative lumen for an electrode assembly.
2. Related Art
There are a variety of medical implants which deliver electrical stimulation to a patient or recipient (“recipient” herein) for a variety of therapeutic benefits. For example, the hair cells of the cochlea of a normal healthy ear convert acoustic signals into nerve impulses. People who are profoundly deaf due to the absence or destruction of cochlea hair cells are unable to derive suitable benefit from conventional hearing aid systems. Prosthetic hearing implant systems have been developed to provide such persons with the ability to perceive sound. Prosthetic hearing implant systems bypass the hair cells in the cochlea to directly deliver electrical stimulation to auditory nerve fibers, thereby allowing the brain to perceive a hearing sensation resembling the natural hearing sensation.
The electrodes implemented in stimulating medical implants vary according to the device and tissue which is to be stimulated. For example, the cochlea is tonotopically mapped and partitioned into regions, with each region being responsive to stimulus signals in a particular frequency range. To accommodate this property of the cochlea, prosthetic hearing implant systems typically include an array of electrodes each constructed and arranged to deliver an appropriate stimulating signal to a particular region of the cochlea.
To achieve an optimal electrode position close to the inside wall of the cochlea, the electrode assembly should assume this desired position upon or immediately following implantation into the cochlea. It is also desirable that the electrode assembly be shaped such that the insertion process causes minimal trauma to the sensitive structures of the cochlea. Usually the electrode assembly is held in a straight configuration at least during the initial stages of the insertion procedure, conforming to the natural shape of the cochlear once implantation is complete.